Introduction to the Muscular System

What are the three types of muscle tissue in the body?

• Skeletal, Smooth, Cardiac

• Nervous, Connective, Epithelial

• Voluntary, Involuntary, Cardiac

• Striated, Non-striated, Cardiac

What are the characteristics of smooth muscle cells?

• Elongated with tapered ends, lack striations, and have a relatively undeveloped sarcoplasmic reticulum

• Short and striated, with a well-developed sarcoplasmic reticulum

• Round and smooth, with a highly developed sarcoplasmic reticulum

• None of the above

In multiunit smooth muscle, fibers occur separately rather than as sheets and are stimulated by neurons and some hormones.

• True

• False

What is a similarity between smooth muscle contraction and skeletal muscle contraction?

• Only smooth muscle involves actin and myosin

• Both types involve reaction between actin and myosin

• Only skeletal muscle uses ATP energy

• Both types are not stimulated by membrane impulses

Which of the following stimulates both smooth and skeletal muscle contraction?

• Acetylcholine (ACh)

• Norepinephrine

• Hormones

• Calcium ions

Fill in the blank: Smooth muscle maintains a contraction longer with the same amount of ____.

• ATP

• oxygen

• calcium

• glucose

True or False: Hormones can stimulate or inhibit contraction of skeletal muscle.

• True

• False

What is one difference between smooth muscle and skeletal muscle contraction?

• Smooth muscle is faster to contract and relax

• Only skeletal muscle can change length without change in tautness

• Smooth muscle is slower to contract and relax

• Both muscles are equally fast to contract and relax

Where is cardiac muscle found?

• In the lungs

• In the heart

• In the brain

• In the liver

Cardiac muscle consists of branching, striated cells that interconnect in ________ networks.

• three-dimensional

• two-dimensional

• linear

• circular